Terms:
SAE International Journal of Commercial Vehicles
AND
12
Show Only

Collections

File Formats

Content Types

Dates

Sectors

Topics

Authors

Publishers

Affiliations

   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Finite Element Modeling of an Energy-Absorbing Guardrail End Terminal

SAE International Journal of Commercial Vehicles

Insurance Institute for Highway Safety, USA-Wen Hu
Virginia Tech, USA-Yunzhu Meng, Costin Daniel Untaroiu
  • Journal Article
  • 02-12-04-0021
Published 2020-02-07 by SAE International in United States
Guardrail end terminals are specifically designed to decelerate vehicles during impact and protect vehicle occupants from severe injuries. The main objective of this research was to develop and validate a Finite Element (FE) model of the ET-Plus, a commonly used energy-absorbing guardrail end terminal. The ET-Plus FE model was created based on publicly available data on ET-Plus dimensions and material properties. The model was validated against the NCHRP-350 crash tests 27-30 and 31-30 by performing crash simulations with a vehicle model at 100 km/h (62 mph) pre-impact velocity. To check the model robustness, crash simulations with vehicle pre-impact velocities from 97 km/h (60 mph) to 113 km/h (70 mph) were also performed. The developed ET-Plus FE model has a high-quality mesh and can replicate the energy-absorbing mechanism. The time histories of the vehicle yaw angle predicted in the FE simulations of the two NCHRP 350 crash tests showed good agreement with the corresponding test data. Additionally, the model was stable in crash simulations with the investigated range of pre-impact velocities, and both post-impact velocities and…
This content contains downloadable datasets
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

A Technique of Estimating Particulate Matter Emission in Non-Road Engine Transient Cycle

SAE International Journal of Commercial Vehicles

Tafe Motors and Tractor Ltd., India-Ajay Nain
  • Journal Article
  • 02-12-04-0019
Published 2020-02-07 by SAE International in United States
Particulates are a major source of emission from diesel engine. They consist of particles of carbon, sulfates, oil, fuel, and water. These constituents are measured by filtering a sample diluted in a partial- or full-flow tunnel and weighing them. It is a general trend for measuring particulate matter (PM) on cycle basis. But 1-D simulation needs complete PM 3-D contour map considering all engine operating region. It is very tedious work for generating PM on each steady-state point on engine test bed. Hence, Filter smoke meter or opacimeter measurements can be used for estimating PM. Filter smoke meters measured the light reflected from a filter paper through which a known volume of exhaust gas was passed. Opacity meters measure light absorbed by a standard column of exhaust. Both equipments measure visible black smoke comparatively at lower expenditure cost. They are designed to control measurement noise, resolution and repeatability with acceptable accuracy level. Oil consumption and contribution of fuel sulfates are also considered in ISO 8178 R49, D2 and C1, India CEV Stage IIIA, India CPCB…
This content contains downloadable datasets
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Empirical Investigation on the Effects of Rolling Resistance and Weight on Fuel Economy of Medium-Duty Trucks

SAE International Journal of Commercial Vehicles

AxleTech, USA-Molly O’Malley
Primus Solutions Inc., USA-Brandon Card
  • Journal Article
  • 02-12-03-0016
Published 2019-08-28 by SAE International in United States
Vehicle rolling resistance and weight are two of the factors that affect fuel economy. The vehicle tire rolling resistance has a more significant influence than aerodynamics drags on fuel economy at lower vehicle speeds, particularly true for medium- and heavy-duty trucks. Less vehicle weight reduces inertia loads, uphill grade resistance, and rolling resistance. The influence of weight on the fuel economy can be considerable particularly in light- to medium-duty truck classes because the weight makes up a larger portion of gross vehicle weight. This article presents an empirical investigation and a numerical analysis of the influences of rolling resistance and weight on the fuel economy of medium-duty trucks. The experimental tests include various tires and payloads applied on a total of 21vehicle configurations over three road profiles. These tests assessed the sensitivity of the vehicle’s fuel economy toward rolling resistance and weight. Several experimental results showed inconsistent and counterintuitive trends of the effects of rolling resistance coefficients and weights on fuel economy. The consequences of rolling resistance and vehicle payload are compound and influenced by…
This content contains downloadable datasets
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Application of Multi-Attribute Weighted Gray Target Decision in Automobile Noise Reduction Scheme Evaluation

SAE International Journal of Commercial Vehicles

Nanjing Institute of Technology, China-Zhendong Zhao
  • Journal Article
  • 02-12-03-0014
Published 2019-07-03 by SAE International in United States
In the selection of automobile noise reduction schemes, the lack of comprehensive quantitative index system and objective evaluation method is a serious problem. In this article, the methods of analytic hierarchy process (AHP) and gray target decision were used to solve the problem. Firstly, AHP and gray target decision method were introduced respectively in detail. Secondly, three automobile noise reduction schemes were illustrated. Four types of data were selected as the decision indexes, and the weight coefficients of all the decision indexes were calculated using the AHP. Then multi-attribute mixed weighted gray target decision model was established. The optimum scheme was obtained by the calculation of the off-target distance and the sorting of the calculation results. The proposed method can quantify the evaluation process and overcome the disadvantages of the traditional analogy method. The example shows that the method is feasible.
This content contains downloadable datasets
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Speed Planning and Prompting System for Commercial Vehicle Based on Real-Time Calculation of Resistance

SAE International Journal of Commercial Vehicles

Wuhan University of Technology, China-Zhaocong Sun, Zhimin Li, Jinyi Xia, Gangfeng Tan
  • Journal Article
  • 02-12-03-0013
Published 2019-06-25 by SAE International in United States
When commercial vehicles drive in a mountainous area, the complex road condition and long slopes cause frequent acceleration and braking, which will use 25% more fuel. And the brake temperature rises rapidly due to continuous braking on the long-distance downslopes, which will make the brake drum fail with the brake temperature exceeding 308°C [1]. Meanwhile, the kinetic energy is wasted during the driving progress on the slopes when the vehicle rolls up and down. Our laboratory built a model that could calculate the distance from the top of the slope, where the driver could release the accelerator pedal. Thus, on the slope, the vehicle uses less fuel when it rolls up and less brakes when down. What we do in this article is use this model in a real vehicle and measure how well it works. Thus, to improve the safety and economy of commercial vehicles on mountainous areas, the Vehicle Speed Planning and Prompting System based on real-time calculation of resistance is established. The system consists of four parts: Hardware on Vehicle, Microcontroller Unit…
This content contains downloadable datasets
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Development of a Standard Testing Method for Vehicle Cabin Air Quality Index

SAE International Journal of Commercial Vehicles

Emissions Analytics, UK-Nick Molden, Sam Boyle
University of California, Riverside, USA-Liem Pham, Kent Johnson, Heejung Jung
  • Journal Article
  • 02-12-02-0012
Published 2019-05-20 by SAE International in United States
Vehicle cabin air quality depends on various parameters such as number of passengers, fan speed, and vehicle speed. In addition to controlling the temperature inside the vehicle, HVAC control system has evolved to improve cabin air quality as well. However, there is no standard test method to ensure reliable and repeatable comparison among different cars. The current study defined Cabin Air Quality Index (CAQI) and proposed a test method to determine CAQI. CAQIparticles showed dependence on the choice of metrics among particle number (PN), particle surface area (PS), and particle mass (PM). CAQIparticles is less than 1 while CAQICO2 is larger than 1. The proposed test method is promising but needs further improvement for smaller coefficient of variations (COVs).
This content contains downloadable datasets
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Improving Multi-Axle Vehicle Steering Coordination Performance Based on the Concept of Instantaneous Wheel Turn Center

SAE International Journal of Commercial Vehicles

GAC Automotive Research & Development Center, China-Bo Wang, Hongshan Zha, Guoqi Zhong, Shijing Weng, Qin Li
Jilin University, China-Pingping Lu
  • Journal Article
  • 02-12-02-0010
Published 2019-03-14 by SAE International in United States
A new concept of instantaneous wheel turn center (IWTC) is proposed to evaluate and improve multi-axle vehicle steering coordination performance. The concept of IWTC and its calculation method are studied. The index named dispersion of IWTC is developed to evaluate the vehicle steering coordination performance quantitatively. The simulation tests based on a three-axle off-road vehicle model are conducted under different vehicle velocities and lateral accelerations. The simulation results show that the turn centers of different wheels are disperse, and the dispersion becomes larger with the increase of vehicle velocities and lateral acceleration. Since suspension has important influences on vehicle steering performance, the genetic algorithm is used to optimize the suspension hard points and bushing stiffness, aiming at minimizing the dispersion of wheel turn centers (DWTC) to improve the vehicle steering coordination performance. The optimization results indicate that the suspension optimization can effectively reduce the DWTC and improve the vehicle steering coordination performance. The proposed wheel turn center method provides an index and tool for the suspension design and optimization in the pre-development phase of the…
This content contains downloadable datasets
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

An Approach for Heavy-Duty Vehicle-Level Engine Brake Performance Evaluation

SAE International Journal of Commercial Vehicles

Navistar, Inc., USA-Peirong Jia
  • Journal Article
  • 02-12-01-0005
Published 2019-01-08 by SAE International in United States
An innovative analysis approach to evaluate heavy-duty vehicle downhill engine brake performance was developed. The vehicle model developed with GT-Drive simulates vehicle downhill control speeds with different engine brake retarding powers, transmission gears, and vehicle weights at sea level or high altitude. The outputs are then used to construct multi-factor parametric design charts. The charts can be used to analyze the vehicle-level engine brake capabilities or compare braking performance difference between different engine brake configurations to quantify the risk of engine retarding power deficiency at both sea level and high altitude downhill driving conditions. The methodology and the models can address the following topics in steady-state operation with a robust engine analysis approach: (1) design criteria of the engine brake in vehicle system integration, (2) vehicle braking capability evaluations, (3) comparison between different engine brakes or different transmissions at both sea level and high altitude, (4) vehicle braking power shortage analysis and risk evaluation, (5) extra absorbed power and energy of service brakes of the vehicle due to retarding power shortage, and (6) comprehensive interactions…
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Design of High-Lift Airfoil for Formula Student Race Car

SAE International Journal of Commercial Vehicles

Ain Shams University, Egypt-Abdelrahman Ibrahim Mahgoub, Hashim El-Zaabalawy, Walid Aboelsoud, Mohamed Abdelaziz
  • Journal Article
  • 02-12-01-0002
Published 2018-12-05 by SAE International in United States
A two-dimensional model of three elements, high-lift airfoil, was designed at a Reynolds number of 106 using computational fluid dynamics (CFD) to generate downforce with good lift-to-drag efficiency for a formula student open-wheel race car basing on the nominal track speeds. The numerical solver uses the Reynolds-averaged Navier-Stokes (RANS) equation model coupled with the Langtry-Menter four-equation transition shear stress transport (SST) turbulence model. Such model adds two further equations to the k − ω SST model resulting in an accurate prediction for the amount of flow separation due to adverse pressure gradient in low Reynolds number flow. The k − ω SST model includes the transport effects into the eddy-viscosity formulation, whereas the two equations of transition momentum thickness Reynolds number and intermittency should further consider transition effects at low Reynolds number. Starting with a baseline design using the understanding of high-lift airfoils, all elements were arranged using an Eppler E421 profile. The lift coefficient was improved by varying the flaps’ overlaps, gaps, and deflection angles sequentially, thus testing 31 rigging combinations. Finally, these data…
This content contains downloadable datasets
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Numerical Analysis of Blast Protection Improvement of an Armored Vehicle Cab by Composite Armors and Anti-Shock Seats

SAE International Journal of Commercial Vehicles

Beijing Mechanical Equipment Institute and Tsinghua University, China-Yan-Peng Dong
Tsinghua University, China-Zhen-Hua Lu
  • Journal Article
  • 02-12-01-0001
Published 2018-12-05 by SAE International in United States
The objective of this article is to evaluate the effects of different blast protective modules to military vehicle structures and occupants. The dynamic responses of the V-shape integral basic armor, the add-on honeycomb sandwich structure module, and the anti-shock seat-dummy system were simulated and analyzed. The improvements of occupant survivability by different protective modules were compared using occupant injury criteria. The integral armored cab can maintain the integrity of the cab body structure. The add-on honeycomb sandwich armor reduces the peak structural deformation and velocity of the cab floor by 34.9% and 47.4%, respectively, compared with the cab with integral armors only. The integral armored cab with the anti-shock seat or the honeycomb sandwich structures reduces the occupant shock responses below the injury criteria. For different blast threat intensities, the selection of appropriate protective modules can meet protection requirements.
This content contains downloadable datasets
Annotation ability available